JPH07324729A - Device for estimating flow rate of supplied powder - Google Patents

Abstract

PURPOSE:To eliminate an external disturbance and calculate the flow rate of powder automatically and under a high precision by a method wherein when the external disturbance occurs, a reset signal is sent to a flow rate estimating filter device, a start signal is sent to a flow rate planning filter device, respectively, and at the same time when the external disturbance is eliminated, a changing-over signal is sent to an output processing device. CONSTITUTION:A flow rate estimating filter device receives an output from a flow rate estimating filter device 61 and stores input data. Then, when a start signal 14ts is received, a calculation processing with a linear planning filter method is carried out to output data in such a way that the stored data is utilized, outwardly inserted and planning is carried out. An output processing device 10t receives outputs from a flow rate estimating filter device 6t and a flow rate planning filter device 9t and normally the output processing device outputs a sum of the former one and the latter one. In the case that an external disturbance occurs, a reset signal 13ts is outputted to the flow rate estimating filter device 6t and concurrently a start signal 14ts is outputted to the flow rate planning filter device 9t.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder supply flow rate estimation device applied to a process for supplying pulverized coal or char by using a batch process in a pressure furnace such as a coal gasification furnace or a pressurized fluidized bed boiler. Regarding

[0002]

2. Description of the Related Art As shown in FIGS. 3 and 4, a two-stage coal gasification furnace is provided with a pulverized coal supply device and a char supply device.

In FIG. 3, a C-type pulverized coal bottle 32C is connected to the rotary feeder 31 of the pulverized coal machine 30. The lower part of the pulverized coal bottle 32C is connected to the upper part of the C-type lock hopper 35C via inlet airtight valves 33C and 34C.
The lower part of the lock hopper 35 is C through an outlet airtight valve 36C.
It is connected to the upper part of the system weighing hopper 37C. A table feeder 38C is provided below the weighing hopper 37C, and is connected to a combustor burner of a coal gasification furnace via the table feeder 38C. C system B between pulverized coal bottle 32C and weighing hopper 37C
A -R pressure equalizing valve 41C and a C-system RM pressure equalizing valve 42C are sequentially passed, and then connected by a pressure equalizing line 40C. A pressure equalizing line 43C is connected to the lock hopper 35C from between the pressure equalizing valves 41C and 42C. Further equalizing valves 41C and 42
A lock hopper pressurized air line 44C is connected between C and the lock hopper 35C.

Further, the pressure reducing exhaust valve 4 is provided in the lock hopper 35C.
A decompression line 45C having 6C is connected. Pulverized coal bottle 32C, lock hopper 35C, and weighing hopper 3
7C is provided with a weighing scale WX. A pressure gauge PX is provided in each of the lock hopper 35C and the weighing hopper 37C. Further, a differential pressure gauge DX is provided between the pulverized coal bottle 32C and the lock hopper 35C, and between the lock hopper 35C and the weighing hopper 37C. The table feeder 38C is provided with a revolution counter N.

The F system connected to the reductor burner has almost the same structure as the C system. Further, the char feeding device has a substantially similar structure as shown in FIG. 50 in the figure
a and 50b are cyclones, 51 is a char secondary recovery device,
52a and 52b are charbins, 53 is charlock hoppers, 54 is char metering hoppers, 55 is a table feeder, 56 is a recycle gas compressor, 57 is a recycle gas buffer tank, 58a and 58b are BR pressure equalizing valves, 5
Reference numeral 9 is an RM equalization valve.

In the above, the operation process of the C system of the pulverized coal supply device is performed as follows. When a predetermined amount of pulverized coal is accumulated in the pulverized coal bottle 32C, the inlet air-tight valve and the BR equalizing valve are opened while the pulverized coal bottle and the lock hopper 35C are at normal pressure, and the pulverized coal is discharged to the lock hopper. At this time, the weighing hopper 37C is pressed to increase the weight. The lock hopper 35C pressurizes with the inlet airtight valve and the outlet airtight valve closed. When the weighing hopper 37C has decreased to a predetermined amount, the lock hopper outlet airtight valve and the RM pressure equalizing valve are opened, and the pulverized coal is discharged from the lock hopper 35C to the weighing hopper. When the dispensing is completed, the outlet airtight valve is closed and the lock hopper pressure is reduced. At this time, the force pulling the pulverized coal bottle 32C is relaxed, and the weight of the bottle apparently increases. The lock hopper pressure returns to normal pressure before returning to.

The other R systems and the char feeding device operate in substantially the same manner.

As described above, each system is a batch process. The supply flow rate estimating device is as shown in FIG.
The output of the table feeder tachometer N of the weighing hopper is sent to the multiplier 62 via the volume flow converter 60. Also,
The output of the bulk specific gravity setting device 61 is sent to the multiplier 62. The output of the multiplier 62 becomes the supply flow rate estimated value 62S.

In the above, the operator has read the outputs of the volume flow converter 60 and the load cell weight scale WX, manually calculated the bulk specific gravity, and set the bulk specific gravity setter 61.

[0010]

The above conventional method for supplying pulverized coal from a pulverized coal bottle under normal pressure to a pressure furnace is such that the lock hopper is first decompressed to receive the pulverized coal from the pulverized coal bottle, It is a batch process in which the operation of applying pressure and sending it to the weighing hopper is repeated. Since the weight of the hopper supported by expansion is measured by the load cell, the reaction force due to the pressure increase / decrease of one's own system or the pressure increase / decrease of other system acts on the measurement data as a disturbance, and the data is There are large fluctuations and irregularities in the data. Therefore, in the past, the bulk specific gravity of pulverized coal was estimated by hand and the weight flow rate was estimated by calculation with the rotational speed of the rotary feeder, but the estimation error is large and it is difficult to automate the manual work. there were. The adoption of other measurement methods also has a drawback in terms of cost performance.

[0011]

The present invention takes the following means in order to solve the above problems.

That is, as the powder supply flow rate estimating device,
A pre-processing filter device that receives the weight signal of the weighing hopper load cell and removes high-frequency noise, and a flow-rate estimation filter device that estimates and calculates the flow rate while receiving the output of the pre-processing filter device and stops the output when a reset signal is input, A flow rate predicting filter device that receives the output of the same flow rate estimating filter device and outputs a flow rate predictive calculation from past data when a start signal is received, and normally receives the output of the flow rate estimating filter device and the flow rate predicting filter device described above. An output processing device that outputs the sum of the latter and, when receiving a switching signal, smoothly switches from the latter output to the former output, powder bin / lock hopper differential pressure signal, the same lock hopper / measurement hopper differential pressure signal And when the disturbance of the output of the pre-processing filter device occurs, the reset signal and the Over it outputs the door signal providing a filter switching device for outputting the switching signal when the disturbance has disappeared.

[0013]

In the above means, the preprocessing filter receives the weight signal of the weighing hopper load cell, removes high frequency noise due to electrical and mechanical vibrations, and outputs it to the estimation filter device. The flow rate estimation filter device estimates and calculates the flow rate from the average slope of the input, and stops the output when the reset signal is input. The flow rate predicting filter device receives and stores the output of the flow rate estimating filter device, and when receiving the start signal, performs a flow rate predicting calculation for extrapolation from the stored data and outputs it. The output processing device receives the outputs of the flow rate estimation filter device and the flow rate prediction filter device, and normally outputs the sum, that is, the output of the former or the latter, and when receiving the switching signal, smoothly switches from the latter output to the former output. Output. The filter switching device receives the powder bin / lock hopper differential pressure signal, the lock hopper / weighing hopper differential pressure signal, and the output of the pretreatment filter device, detects the disturbance occurrence, and when the disturbance occurs, sends it to the flow rate estimation filter device. A reset signal and a start signal are sent to the flow rate predicting filter device, respectively, and a switching signal is sent to the output processing device when the disturbance disappears.

In this way, the electrical and mechanical high frequency noise is removed and the influence of disturbance is removed, and the powder flow rate supplied from the weighing hopper is automatically calculated with high accuracy.

[0015]

【Example】

(1) A first embodiment in which the present invention described above is applied to the char feeding device of FIG. 4 will be described with reference to FIGS.

In FIG. 4 and FIG. 1, the signal of the differential pressure gauge DX between the charbin 52a and the lock hopper 53, that is, the differential pressure signal 1ts-1 of the Charvin lock hopper, passes through the threshold value processor 2t-1, and the switch 3t. Sent to. Similarly, the signal of the differential pressure gauge DX between the charbine 52b and the lock hopper 53, that is, the differential pressure signal 1ts of the charbine lock hopper.
-2 is sent to the switch 3t via the threshold value processor 2t-2. The signal of the differential pressure gauge DX between the charbin 52b and the lock hopper 53, that is, the differential pressure signal 8ts of the charvin lock hopper is sent to the switch 3t via the threshold value processor 4t. The signal of the load cell weight scale WX of the weighing hopper 54, that is, the weighing hopper load cell weight signal 11ts is sequentially sent to the switch 3t through the preprocessing filter device 5t and the inclination threshold processor 7t. In addition, the pretreatment filter device 5t
Is sent to the flow rate prediction filter device 9t through the flow rate estimation filter device 6t. Further, the outputs of the flow rate estimation filter device 6t and the flow rate estimation filter device 9t are sent to the output processing device 10t.

Reset signal 13ts from the switch 3t,
The start signal 14ts and the switching signal 15ts are sent to the flow rate estimation filter device 6t, the flow rate prediction filter device 9t, and the output processing device 10t, respectively. Further, the load changing signal 12ts is sent to the flow rate estimation filter device 6t. In the above, the threshold value processors 2t-1, 2t-2, 4t,
The gradient threshold processor 7t and the switch 3t are the filter switching device 1t.

In the above, the preprocessing filter device 5t receives the weighing hopper load cell weight signal 11ts and performs arithmetic processing by the moving average method so as to remove high frequency noise due to electrical and mechanical vibrations.

The flow rate estimating filter device 6t receives the output from the pre-processing filter device 5t, removes low-frequency disturbances mainly due to process disturbances, and estimates the average slope to convert it into a flow rate, and gradually decreases the gain. It performs arithmetic processing by the successive least squares filter method used and outputs it. At this time,
The gain is fixed when the load changing signal 12ts is received. When receiving the reset signal 13ts, the output is stopped. The flow rate prediction filter device receives the output from the flow rate estimation filter device 6t, stores the input data, and when the start signal 14ts is received, the stored data is used and extrapolation is performed to perform the prediction by the linear prediction filter method. Performs arithmetic processing and outputs. Output processing device 10
t receives the outputs of the flow rate estimation filter device 6t and the flow rate estimation filter device 9t, and normally outputs the sum of the former and the latter. That is, the former output is output while the former is outputting, and the latter output is output while the latter is outputting. When the switching signal 15ts is received, the latter output is smoothly output to the former output. That is, bumpless processing is performed and output. These outputs are the supply flow rate estimation signal 10ts of the char supply device.
Becomes

On the other hand, each threshold value processor 2t-1, 2t-
2 and 4t normally output an OFF signal, and output an ON signal when the input exceeds a predetermined value. Further, the inclination threshold processor 7t normally outputs an OFF signal, and outputs an ON signal when the input inclination exceeds a predetermined value. The switch 3t receives the outputs of the threshold value processors 2t-1, 2t-2, 4t and the inclination threshold value processor 7t, detects the presence or absence of disturbance, and when there is disturbance, the flow rate estimation filter device 6t. The reset signal 13ts is output to and the start signal 14ts is output to the flow rate prediction filter device 9t. When the disturbance has disappeared, the switching signal 15ts is output to the output processing device 10t.

As described above, the estimated supply flow rate of char from the batch-operated char feeder is stably and automatically calculated with high accuracy.

Further, when the gradually decreasing gain is used as in the calculation by the above-mentioned successive least squares filter method, there is a drawback that the followability to the load change is deteriorated, but the gain change is fixed during the load change. As a result, the followability to a load change is improved while maintaining the stability in the steady state.

Although the moving average filter method is used in the preprocessing filter device 5t in the above, a low pass filter method or the like may be used. Further, the flow rate estimation filter device 6t
In the above, the successive least squares filter method is used, but a differential filter method, a moving gradient filter method, or the like may be used. Furthermore, although the linear prediction filter method is used in the flow rate prediction filter device 9t, a function approximation method, an autoregressive moving average model method, or the like may be used. (2) A second embodiment in which the present invention described above is applied to a C-based and R-based pulverized coal supply device will be described with reference to FIGS. 2 and 3.

C system pulverized coal bottle / lock hopper differential pressure signal 1
The cs is sent to the switch 3C via the threshold processor 2C. The C-system weighing hopper load cell weight signal 11cs is sequentially sent to the flow rate predicting filter apparatus 9C through the movement processing filter apparatus 5C and the flow rate estimating filter apparatus 6c. Further, the flow rate estimation filter device 6C and the flow rate prediction filter device 9C
Is sent to the output processing device 10C. The output of the pre-processing filter device 5C passes through the slope threshold value processor 7C and then the switch 3
Sent to C. The R-system lock hopper / metering hopper differential pressure signal 8rs passes through the threshold value processor 4R and each switching device 3C03.
Sent to R. The load changing signal 12rs is sent to the flow rate estimation filter device 6C. Reset signal 1 of switch 3C
3cs, start signal 14cs and switching signal 15cs
Are sent to the flow rate estimation filter device 6C, the flow rate estimation filter device 9C, and the output processing device 10C, respectively.
The output processing device 10C is a C-system pulverized coal supply flow rate estimation signal 1
Outputs 0cs.

R system pulverized coal bottle / lock hopper differential pressure signal 1
rs is sent to the switch 3R via the threshold processor 2R. The R-system weighing hopper load cell weight signal 11rs is sequentially sent to the flow rate predicting filter device 9R through the preprocessing filter device 5R and the flow rate estimating filter device 6R. Further, the load changing signal 12rs is sent to the flow rate estimation filter device 6R. Further, the reset signal 13rs, the start signal 14rs, and the switching signal 15rs of the switch 3R are the flow rate estimation filter device 6R and the flow rate prediction filter device 9R, respectively.
And to the output processing device 10R. The outputs of the flow rate estimation filter device 6R and the flow rate estimation filter device 9R are sent to the output processing device 10R. The output processing device 10R is R
A supply flow rate estimation signal 10rs of the pulverized coal is output.

In the above, the function and effect are almost the same as those of the above-mentioned embodiment, and therefore the explanation thereof will be omitted.

[0027]

As described above, according to the present invention, even when the weight data suddenly changes such as when the powder is discharged from the lock hopper to the weighing hopper in the batch process, these disturbances cause the disturbance. During the period when the signal is disturbed, the estimation by the flow rate estimation filter device is reset to make the output zero, and the estimated value is extrapolated and complemented by the flow rate estimation filter device to switch the result to bumpless. A small supply flow rate estimation signal can be obtained.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of a first embodiment of the present invention.

FIG. 2 is a configuration block diagram of a second embodiment of the present invention.

FIG. 3 is a configuration system diagram of a C-R pulverized coal supply device of a conventional example and a second embodiment of the present invention.

FIG. 4 is a configuration system diagram of a char feeding device of the conventional example and the first embodiment of the present invention.

FIG. 5 is an explanatory block diagram of the conventional example.

[Explanation of symbols]

1ts-1 NO. 1 Charvin lock hopper differential pressure signal 1ts-2 NO. 2 Charbin / Lock hopper differential pressure signal 8ts Lock hopper / weighing hopper differential pressure signal 11ts Weighing hopper load cell weight signal 5t Pre-processing filter device 6t Flow rate estimating filter device 9t Flow rate predicting filter device 10t Output processing device 16t Filter switching device

Claims (1)

[Claims] 1. A pretreatment filter device for receiving a weight signal of a weighing hopper load cell to remove high frequency noise, and a flow amount for estimating and calculating the flow amount of the output of the pretreatment filter device and stopping the output when a reset signal is input. The estimation filter device, the flow rate estimation filter device that receives the output of the flow rate estimation filter device and outputs the flow rate prediction calculation from the past data when the start signal is received, and the output of the flow rate estimation filter device and the flow rate estimation filter device. Receiving normally outputs the sum of the former and the latter, and when receiving the switching signal, the output processing device that smoothly switches from the latter output to the former output, the powder bin lock hopper differential pressure signal, the lock hopper When the disturbance is generated by receiving the weighing hopper differential pressure signal and the output of the pretreatment filter device, the reset A powder supply flow rate estimating device, comprising: a filter switching device that outputs a signal and a start signal and outputs the switching signal when the disturbance disappears.